In recognition of Fire Service Week 2016, NATION Online will be reproducing a series of articles on fire safety and fire prevention.
SO YOU want to purchase an extinguisher for your home – the problem is there are several types out there and each is for a different purpose.
Extinguishers are rated by Underwriters’ Laboratory (UL) based on their testing for different types of fire.
Class A is best for normal combustibles like paper, wood, rubber, plastic, or cloth. This type uses pressurised water or dry chemicals to put the fire out.
Class A extinguishers have an additional numeric rating for the amount of water to which the extinguisher is equivalent. Each unit equals 1.25 gallons of water.
An extinguisher rated 1-A would extinguish normal combustibles with a capacity equal to 1.25 gallons of water.
A rating of 4-A indicates an equivalency to five gallons of water.
Class B is used to combat flammable liquids, grease, gas, oil, petroleum products, oil-based paint, lacquer, and solvents.
This type may contain dry chemicals or carbon dioxide.
Class B extinguishers have a numeric rating but it doesn’t mean the same thing as the numeric rating of a Class A appliance.
Class B extinguishers are rated according to how many square feet of fire could be extinguished by a non-expert using that type.
Thus a rating of 10-B would mean that ten square feet of a class B fire will be extinguished – an area slightly larger than three feet by three feet.
Think about how much fire you plan to fight by yourself.
Ten square feet of fire would be too much for a non-professional to take on except to provide a means of escape from the area.
Use Class C fire extinguishers to combat electrical fires.
These occur in wiring, fuse boxes, and electrical equipment including computers. There may be dry chemicals or CO2 inside.
Note there is no numeric rating for this kind of extinguisher.
Class D extinguishers are a specialised class used for flammable metals like magnesium and sodium. They should not be used around the home.
There are multi-class extinguishers as well, capable of handling more than one type of fire. They are classified as “AB-C” or “B-C” using the above guidelines.
There are also extinguishers that are made specifically for use over stoves. They contain bicarbonate of soda or baking soda. The powder inside is released automatically when the temperature reaches 277 degrees Fahrenheit.
In the home, it is better to have a small extinguisher conveniently placed than to have a large, heavy extinguisher that must be brought to the scene.
The most common home and vehicle fire extinguisher is rated 5-B-C. These versions are small, weigh less than two pounds, and easy for anyone to use.
There are even smaller 2-B-C extinguishers available. Remember that the intent should never be to put out a large fire.
The goal should be to extinguish a small fire or, in a real emergency, to clear a path as an escape route.
